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-rw-r--r--vendor/github.com/authzed/cel-go/checker/checker.go696
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diff --git a/vendor/github.com/authzed/cel-go/checker/checker.go b/vendor/github.com/authzed/cel-go/checker/checker.go
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+++ b/vendor/github.com/authzed/cel-go/checker/checker.go
@@ -0,0 +1,696 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package checker defines functions to type-checked a parsed expression
+// against a set of identifier and function declarations.
+package checker
+
+import (
+ "fmt"
+ "reflect"
+
+ "github.com/authzed/cel-go/common"
+ "github.com/authzed/cel-go/common/ast"
+ "github.com/authzed/cel-go/common/containers"
+ "github.com/authzed/cel-go/common/decls"
+ "github.com/authzed/cel-go/common/operators"
+ "github.com/authzed/cel-go/common/types"
+ "github.com/authzed/cel-go/common/types/ref"
+)
+
+type checker struct {
+ *ast.AST
+ ast.ExprFactory
+ env *Env
+ errors *typeErrors
+ mappings *mapping
+ freeTypeVarCounter int
+}
+
+// Check performs type checking, giving a typed AST.
+//
+// The input is a parsed AST and an env which encapsulates type binding of variables,
+// declarations of built-in functions, descriptions of protocol buffers, and a registry for
+// errors.
+//
+// Returns a type-checked AST, which might not be usable if there are errors in the error
+// registry.
+func Check(parsed *ast.AST, source common.Source, env *Env) (*ast.AST, *common.Errors) {
+ errs := common.NewErrors(source)
+ typeMap := make(map[int64]*types.Type)
+ refMap := make(map[int64]*ast.ReferenceInfo)
+ c := checker{
+ AST: ast.NewCheckedAST(parsed, typeMap, refMap),
+ ExprFactory: ast.NewExprFactory(),
+ env: env,
+ errors: &typeErrors{errs: errs},
+ mappings: newMapping(),
+ freeTypeVarCounter: 0,
+ }
+ c.check(c.Expr())
+
+ // Walk over the final type map substituting any type parameters either by their bound value
+ // or by DYN.
+ for id, t := range c.TypeMap() {
+ c.SetType(id, substitute(c.mappings, t, true))
+ }
+ return c.AST, errs
+}
+
+func (c *checker) check(e ast.Expr) {
+ if e == nil {
+ return
+ }
+ switch e.Kind() {
+ case ast.LiteralKind:
+ literal := ref.Val(e.AsLiteral())
+ switch literal.Type() {
+ case types.BoolType, types.BytesType, types.DoubleType, types.IntType,
+ types.NullType, types.StringType, types.UintType:
+ c.setType(e, literal.Type().(*types.Type))
+ default:
+ c.errors.unexpectedASTType(e.ID(), c.location(e), "literal", literal.Type().TypeName())
+ }
+ case ast.IdentKind:
+ c.checkIdent(e)
+ case ast.SelectKind:
+ c.checkSelect(e)
+ case ast.CallKind:
+ c.checkCall(e)
+ case ast.ListKind:
+ c.checkCreateList(e)
+ case ast.MapKind:
+ c.checkCreateMap(e)
+ case ast.StructKind:
+ c.checkCreateStruct(e)
+ case ast.ComprehensionKind:
+ c.checkComprehension(e)
+ default:
+ c.errors.unexpectedASTType(e.ID(), c.location(e), "unspecified", reflect.TypeOf(e).Name())
+ }
+}
+
+func (c *checker) checkIdent(e ast.Expr) {
+ identName := e.AsIdent()
+ // Check to see if the identifier is declared.
+ if ident := c.env.LookupIdent(identName); ident != nil {
+ c.setType(e, ident.Type())
+ c.setReference(e, ast.NewIdentReference(ident.Name(), ident.Value()))
+ // Overwrite the identifier with its fully qualified name.
+ e.SetKindCase(c.NewIdent(e.ID(), ident.Name()))
+ return
+ }
+
+ c.setType(e, types.ErrorType)
+ c.errors.undeclaredReference(e.ID(), c.location(e), c.env.container.Name(), identName)
+}
+
+func (c *checker) checkSelect(e ast.Expr) {
+ sel := e.AsSelect()
+ // Before traversing down the tree, try to interpret as qualified name.
+ qname, found := containers.ToQualifiedName(e)
+ if found {
+ ident := c.env.LookupIdent(qname)
+ if ident != nil {
+ // We don't check for a TestOnly expression here since the `found` result is
+ // always going to be false for TestOnly expressions.
+
+ // Rewrite the node to be a variable reference to the resolved fully-qualified
+ // variable name.
+ c.setType(e, ident.Type())
+ c.setReference(e, ast.NewIdentReference(ident.Name(), ident.Value()))
+ e.SetKindCase(c.NewIdent(e.ID(), ident.Name()))
+ return
+ }
+ }
+
+ resultType := c.checkSelectField(e, sel.Operand(), sel.FieldName(), false)
+ if sel.IsTestOnly() {
+ resultType = types.BoolType
+ }
+ c.setType(e, substitute(c.mappings, resultType, false))
+}
+
+func (c *checker) checkOptSelect(e ast.Expr) {
+ // Collect metadata related to the opt select call packaged by the parser.
+ call := e.AsCall()
+ operand := call.Args()[0]
+ field := call.Args()[1]
+ fieldName, isString := maybeUnwrapString(field)
+ if !isString {
+ c.errors.notAnOptionalFieldSelection(field.ID(), c.location(field), field)
+ return
+ }
+
+ // Perform type-checking using the field selection logic.
+ resultType := c.checkSelectField(e, operand, fieldName, true)
+ c.setType(e, substitute(c.mappings, resultType, false))
+ c.setReference(e, ast.NewFunctionReference("select_optional_field"))
+}
+
+func (c *checker) checkSelectField(e, operand ast.Expr, field string, optional bool) *types.Type {
+ // Interpret as field selection, first traversing down the operand.
+ c.check(operand)
+ operandType := substitute(c.mappings, c.getType(operand), false)
+
+ // If the target type is 'optional', unwrap it for the sake of this check.
+ targetType, isOpt := maybeUnwrapOptional(operandType)
+
+ // Assume error type by default as most types do not support field selection.
+ resultType := types.ErrorType
+ switch targetType.Kind() {
+ case types.MapKind:
+ // Maps yield their value type as the selection result type.
+ resultType = targetType.Parameters()[1]
+ case types.StructKind:
+ // Objects yield their field type declaration as the selection result type, but only if
+ // the field is defined.
+ messageType := targetType
+ if fieldType, found := c.lookupFieldType(e.ID(), messageType.TypeName(), field); found {
+ resultType = fieldType
+ }
+ case types.TypeParamKind:
+ // Set the operand type to DYN to prevent assignment to a potentially incorrect type
+ // at a later point in type-checking. The isAssignable call will update the type
+ // substitutions for the type param under the covers.
+ c.isAssignable(types.DynType, targetType)
+ // Also, set the result type to DYN.
+ resultType = types.DynType
+ default:
+ // Dynamic / error values are treated as DYN type. Errors are handled this way as well
+ // in order to allow forward progress on the check.
+ if !isDynOrError(targetType) {
+ c.errors.typeDoesNotSupportFieldSelection(e.ID(), c.location(e), targetType)
+ }
+ resultType = types.DynType
+ }
+
+ // If the target type was optional coming in, then the result must be optional going out.
+ if isOpt || optional {
+ return types.NewOptionalType(resultType)
+ }
+ return resultType
+}
+
+func (c *checker) checkCall(e ast.Expr) {
+ // Note: similar logic exists within the `interpreter/planner.go`. If making changes here
+ // please consider the impact on planner.go and consolidate implementations or mirror code
+ // as appropriate.
+ call := e.AsCall()
+ fnName := call.FunctionName()
+ if fnName == operators.OptSelect {
+ c.checkOptSelect(e)
+ return
+ }
+
+ args := call.Args()
+ // Traverse arguments.
+ for _, arg := range args {
+ c.check(arg)
+ }
+
+ // Regular static call with simple name.
+ if !call.IsMemberFunction() {
+ // Check for the existence of the function.
+ fn := c.env.LookupFunction(fnName)
+ if fn == nil {
+ c.errors.undeclaredReference(e.ID(), c.location(e), c.env.container.Name(), fnName)
+ c.setType(e, types.ErrorType)
+ return
+ }
+ // Overwrite the function name with its fully qualified resolved name.
+ e.SetKindCase(c.NewCall(e.ID(), fn.Name(), args...))
+ // Check to see whether the overload resolves.
+ c.resolveOverloadOrError(e, fn, nil, args)
+ return
+ }
+
+ // If a receiver 'target' is present, it may either be a receiver function, or a namespaced
+ // function, but not both. Given a.b.c() either a.b.c is a function or c is a function with
+ // target a.b.
+ //
+ // Check whether the target is a namespaced function name.
+ target := call.Target()
+ qualifiedPrefix, maybeQualified := containers.ToQualifiedName(target)
+ if maybeQualified {
+ maybeQualifiedName := qualifiedPrefix + "." + fnName
+ fn := c.env.LookupFunction(maybeQualifiedName)
+ if fn != nil {
+ // The function name is namespaced and so preserving the target operand would
+ // be an inaccurate representation of the desired evaluation behavior.
+ // Overwrite with fully-qualified resolved function name sans receiver target.
+ e.SetKindCase(c.NewCall(e.ID(), fn.Name(), args...))
+ c.resolveOverloadOrError(e, fn, nil, args)
+ return
+ }
+ }
+
+ // Regular instance call.
+ c.check(target)
+ fn := c.env.LookupFunction(fnName)
+ // Function found, attempt overload resolution.
+ if fn != nil {
+ c.resolveOverloadOrError(e, fn, target, args)
+ return
+ }
+ // Function name not declared, record error.
+ c.setType(e, types.ErrorType)
+ c.errors.undeclaredReference(e.ID(), c.location(e), c.env.container.Name(), fnName)
+}
+
+func (c *checker) resolveOverloadOrError(
+ e ast.Expr, fn *decls.FunctionDecl, target ast.Expr, args []ast.Expr) {
+ // Attempt to resolve the overload.
+ resolution := c.resolveOverload(e, fn, target, args)
+ // No such overload, error noted in the resolveOverload call, type recorded here.
+ if resolution == nil {
+ c.setType(e, types.ErrorType)
+ return
+ }
+ // Overload found.
+ c.setType(e, resolution.Type)
+ c.setReference(e, resolution.Reference)
+}
+
+func (c *checker) resolveOverload(
+ call ast.Expr, fn *decls.FunctionDecl, target ast.Expr, args []ast.Expr) *overloadResolution {
+
+ var argTypes []*types.Type
+ if target != nil {
+ argTypes = append(argTypes, c.getType(target))
+ }
+ for _, arg := range args {
+ argTypes = append(argTypes, c.getType(arg))
+ }
+
+ var resultType *types.Type
+ var checkedRef *ast.ReferenceInfo
+ for _, overload := range fn.OverloadDecls() {
+ // Determine whether the overload is currently considered.
+ if c.env.isOverloadDisabled(overload.ID()) {
+ continue
+ }
+
+ // Ensure the call style for the overload matches.
+ if (target == nil && overload.IsMemberFunction()) ||
+ (target != nil && !overload.IsMemberFunction()) {
+ // not a compatible call style.
+ continue
+ }
+
+ // Alternative type-checking behavior when the logical operators are compacted into
+ // variadic AST representations.
+ if fn.Name() == operators.LogicalAnd || fn.Name() == operators.LogicalOr {
+ checkedRef = ast.NewFunctionReference(overload.ID())
+ for i, argType := range argTypes {
+ if !c.isAssignable(argType, types.BoolType) {
+ c.errors.typeMismatch(
+ args[i].ID(),
+ c.locationByID(args[i].ID()),
+ types.BoolType,
+ argType)
+ resultType = types.ErrorType
+ }
+ }
+ if isError(resultType) {
+ return nil
+ }
+ return newResolution(checkedRef, types.BoolType)
+ }
+
+ overloadType := newFunctionType(overload.ResultType(), overload.ArgTypes()...)
+ typeParams := overload.TypeParams()
+ if len(typeParams) != 0 {
+ // Instantiate overload's type with fresh type variables.
+ substitutions := newMapping()
+ for _, typePar := range typeParams {
+ substitutions.add(types.NewTypeParamType(typePar), c.newTypeVar())
+ }
+ overloadType = substitute(substitutions, overloadType, false)
+ }
+
+ candidateArgTypes := overloadType.Parameters()[1:]
+ if c.isAssignableList(argTypes, candidateArgTypes) {
+ if checkedRef == nil {
+ checkedRef = ast.NewFunctionReference(overload.ID())
+ } else {
+ checkedRef.AddOverload(overload.ID())
+ }
+
+ // First matching overload, determines result type.
+ fnResultType := substitute(c.mappings, overloadType.Parameters()[0], false)
+ if resultType == nil {
+ resultType = fnResultType
+ } else if !isDyn(resultType) && !fnResultType.IsExactType(resultType) {
+ resultType = types.DynType
+ }
+ }
+ }
+
+ if resultType == nil {
+ for i, argType := range argTypes {
+ argTypes[i] = substitute(c.mappings, argType, true)
+ }
+ c.errors.noMatchingOverload(call.ID(), c.location(call), fn.Name(), argTypes, target != nil)
+ return nil
+ }
+
+ return newResolution(checkedRef, resultType)
+}
+
+func (c *checker) checkCreateList(e ast.Expr) {
+ create := e.AsList()
+ var elemsType *types.Type
+ optionalIndices := create.OptionalIndices()
+ optionals := make(map[int32]bool, len(optionalIndices))
+ for _, optInd := range optionalIndices {
+ optionals[optInd] = true
+ }
+ for i, e := range create.Elements() {
+ c.check(e)
+ elemType := c.getType(e)
+ if optionals[int32(i)] {
+ var isOptional bool
+ elemType, isOptional = maybeUnwrapOptional(elemType)
+ if !isOptional && !isDyn(elemType) {
+ c.errors.typeMismatch(e.ID(), c.location(e), types.NewOptionalType(elemType), elemType)
+ }
+ }
+ elemsType = c.joinTypes(e, elemsType, elemType)
+ }
+ if elemsType == nil {
+ // If the list is empty, assign free type var to elem type.
+ elemsType = c.newTypeVar()
+ }
+ c.setType(e, types.NewListType(elemsType))
+}
+
+func (c *checker) checkCreateMap(e ast.Expr) {
+ mapVal := e.AsMap()
+ var mapKeyType *types.Type
+ var mapValueType *types.Type
+ for _, e := range mapVal.Entries() {
+ entry := e.AsMapEntry()
+ key := entry.Key()
+ c.check(key)
+ mapKeyType = c.joinTypes(key, mapKeyType, c.getType(key))
+
+ val := entry.Value()
+ c.check(val)
+ valType := c.getType(val)
+ if entry.IsOptional() {
+ var isOptional bool
+ valType, isOptional = maybeUnwrapOptional(valType)
+ if !isOptional && !isDyn(valType) {
+ c.errors.typeMismatch(val.ID(), c.location(val), types.NewOptionalType(valType), valType)
+ }
+ }
+ mapValueType = c.joinTypes(val, mapValueType, valType)
+ }
+ if mapKeyType == nil {
+ // If the map is empty, assign free type variables to typeKey and value type.
+ mapKeyType = c.newTypeVar()
+ mapValueType = c.newTypeVar()
+ }
+ c.setType(e, types.NewMapType(mapKeyType, mapValueType))
+}
+
+func (c *checker) checkCreateStruct(e ast.Expr) {
+ msgVal := e.AsStruct()
+ // Determine the type of the message.
+ resultType := types.ErrorType
+ ident := c.env.LookupIdent(msgVal.TypeName())
+ if ident == nil {
+ c.errors.undeclaredReference(
+ e.ID(), c.location(e), c.env.container.Name(), msgVal.TypeName())
+ c.setType(e, types.ErrorType)
+ return
+ }
+ // Ensure the type name is fully qualified in the AST.
+ typeName := ident.Name()
+ if msgVal.TypeName() != typeName {
+ e.SetKindCase(c.NewStruct(e.ID(), typeName, msgVal.Fields()))
+ msgVal = e.AsStruct()
+ }
+ c.setReference(e, ast.NewIdentReference(typeName, nil))
+ identKind := ident.Type().Kind()
+ if identKind != types.ErrorKind {
+ if identKind != types.TypeKind {
+ c.errors.notAType(e.ID(), c.location(e), ident.Type().DeclaredTypeName())
+ } else {
+ resultType = ident.Type().Parameters()[0]
+ // Backwards compatibility test between well-known types and message types
+ // In this context, the type is being instantiated by its protobuf name which
+ // is not ideal or recommended, but some users expect this to work.
+ if isWellKnownType(resultType) {
+ typeName = getWellKnownTypeName(resultType)
+ } else if resultType.Kind() == types.StructKind {
+ typeName = resultType.DeclaredTypeName()
+ } else {
+ c.errors.notAMessageType(e.ID(), c.location(e), resultType.DeclaredTypeName())
+ resultType = types.ErrorType
+ }
+ }
+ }
+ c.setType(e, resultType)
+
+ // Check the field initializers.
+ for _, f := range msgVal.Fields() {
+ field := f.AsStructField()
+ fieldName := field.Name()
+ value := field.Value()
+ c.check(value)
+
+ fieldType := types.ErrorType
+ ft, found := c.lookupFieldType(f.ID(), typeName, fieldName)
+ if found {
+ fieldType = ft
+ }
+
+ valType := c.getType(value)
+ if field.IsOptional() {
+ var isOptional bool
+ valType, isOptional = maybeUnwrapOptional(valType)
+ if !isOptional && !isDyn(valType) {
+ c.errors.typeMismatch(value.ID(), c.location(value), types.NewOptionalType(valType), valType)
+ }
+ }
+ if !c.isAssignable(fieldType, valType) {
+ c.errors.fieldTypeMismatch(f.ID(), c.locationByID(f.ID()), fieldName, fieldType, valType)
+ }
+ }
+}
+
+func (c *checker) checkComprehension(e ast.Expr) {
+ comp := e.AsComprehension()
+ c.check(comp.IterRange())
+ c.check(comp.AccuInit())
+ accuType := c.getType(comp.AccuInit())
+ rangeType := substitute(c.mappings, c.getType(comp.IterRange()), false)
+ var varType *types.Type
+
+ switch rangeType.Kind() {
+ case types.ListKind:
+ varType = rangeType.Parameters()[0]
+ case types.MapKind:
+ // Ranges over the keys.
+ varType = rangeType.Parameters()[0]
+ case types.DynKind, types.ErrorKind, types.TypeParamKind:
+ // Set the range type to DYN to prevent assignment to a potentially incorrect type
+ // at a later point in type-checking. The isAssignable call will update the type
+ // substitutions for the type param under the covers.
+ c.isAssignable(types.DynType, rangeType)
+ // Set the range iteration variable to type DYN as well.
+ varType = types.DynType
+ default:
+ c.errors.notAComprehensionRange(comp.IterRange().ID(), c.location(comp.IterRange()), rangeType)
+ varType = types.ErrorType
+ }
+
+ // Create a scope for the comprehension since it has a local accumulation variable.
+ // This scope will contain the accumulation variable used to compute the result.
+ c.env = c.env.enterScope()
+ c.env.AddIdents(decls.NewVariable(comp.AccuVar(), accuType))
+ // Create a block scope for the loop.
+ c.env = c.env.enterScope()
+ c.env.AddIdents(decls.NewVariable(comp.IterVar(), varType))
+ // Check the variable references in the condition and step.
+ c.check(comp.LoopCondition())
+ c.assertType(comp.LoopCondition(), types.BoolType)
+ c.check(comp.LoopStep())
+ c.assertType(comp.LoopStep(), accuType)
+ // Exit the loop's block scope before checking the result.
+ c.env = c.env.exitScope()
+ c.check(comp.Result())
+ // Exit the comprehension scope.
+ c.env = c.env.exitScope()
+ c.setType(e, substitute(c.mappings, c.getType(comp.Result()), false))
+}
+
+// Checks compatibility of joined types, and returns the most general common type.
+func (c *checker) joinTypes(e ast.Expr, previous, current *types.Type) *types.Type {
+ if previous == nil {
+ return current
+ }
+ if c.isAssignable(previous, current) {
+ return mostGeneral(previous, current)
+ }
+ if c.dynAggregateLiteralElementTypesEnabled() {
+ return types.DynType
+ }
+ c.errors.typeMismatch(e.ID(), c.location(e), previous, current)
+ return types.ErrorType
+}
+
+func (c *checker) dynAggregateLiteralElementTypesEnabled() bool {
+ return c.env.aggLitElemType == dynElementType
+}
+
+func (c *checker) newTypeVar() *types.Type {
+ id := c.freeTypeVarCounter
+ c.freeTypeVarCounter++
+ return types.NewTypeParamType(fmt.Sprintf("_var%d", id))
+}
+
+func (c *checker) isAssignable(t1, t2 *types.Type) bool {
+ subs := isAssignable(c.mappings, t1, t2)
+ if subs != nil {
+ c.mappings = subs
+ return true
+ }
+
+ return false
+}
+
+func (c *checker) isAssignableList(l1, l2 []*types.Type) bool {
+ subs := isAssignableList(c.mappings, l1, l2)
+ if subs != nil {
+ c.mappings = subs
+ return true
+ }
+
+ return false
+}
+
+func maybeUnwrapString(e ast.Expr) (string, bool) {
+ switch e.Kind() {
+ case ast.LiteralKind:
+ literal := e.AsLiteral()
+ switch v := literal.(type) {
+ case types.String:
+ return string(v), true
+ }
+ }
+ return "", false
+}
+
+func (c *checker) setType(e ast.Expr, t *types.Type) {
+ if old, found := c.TypeMap()[e.ID()]; found && !old.IsExactType(t) {
+ c.errors.incompatibleType(e.ID(), c.location(e), e, old, t)
+ return
+ }
+ c.SetType(e.ID(), t)
+}
+
+func (c *checker) getType(e ast.Expr) *types.Type {
+ return c.TypeMap()[e.ID()]
+}
+
+func (c *checker) setReference(e ast.Expr, r *ast.ReferenceInfo) {
+ if old, found := c.ReferenceMap()[e.ID()]; found && !old.Equals(r) {
+ c.errors.referenceRedefinition(e.ID(), c.location(e), e, old, r)
+ return
+ }
+ c.SetReference(e.ID(), r)
+}
+
+func (c *checker) assertType(e ast.Expr, t *types.Type) {
+ if !c.isAssignable(t, c.getType(e)) {
+ c.errors.typeMismatch(e.ID(), c.location(e), t, c.getType(e))
+ }
+}
+
+type overloadResolution struct {
+ Type *types.Type
+ Reference *ast.ReferenceInfo
+}
+
+func newResolution(r *ast.ReferenceInfo, t *types.Type) *overloadResolution {
+ return &overloadResolution{
+ Reference: r,
+ Type: t,
+ }
+}
+
+func (c *checker) location(e ast.Expr) common.Location {
+ return c.locationByID(e.ID())
+}
+
+func (c *checker) locationByID(id int64) common.Location {
+ return c.SourceInfo().GetStartLocation(id)
+}
+
+func (c *checker) lookupFieldType(exprID int64, structType, fieldName string) (*types.Type, bool) {
+ if _, found := c.env.provider.FindStructType(structType); !found {
+ // This should not happen, anyway, report an error.
+ c.errors.unexpectedFailedResolution(exprID, c.locationByID(exprID), structType)
+ return nil, false
+ }
+
+ if ft, found := c.env.provider.FindStructFieldType(structType, fieldName); found {
+ return ft.Type, found
+ }
+
+ c.errors.undefinedField(exprID, c.locationByID(exprID), fieldName)
+ return nil, false
+}
+
+func isWellKnownType(t *types.Type) bool {
+ switch t.Kind() {
+ case types.AnyKind, types.TimestampKind, types.DurationKind, types.DynKind, types.NullTypeKind:
+ return true
+ case types.BoolKind, types.BytesKind, types.DoubleKind, types.IntKind, types.StringKind, types.UintKind:
+ return t.IsAssignableType(types.NullType)
+ case types.ListKind:
+ return t.Parameters()[0] == types.DynType
+ case types.MapKind:
+ return t.Parameters()[0] == types.StringType && t.Parameters()[1] == types.DynType
+ }
+ return false
+}
+
+func getWellKnownTypeName(t *types.Type) string {
+ if name, found := wellKnownTypes[t.Kind()]; found {
+ return name
+ }
+ return ""
+}
+
+var (
+ wellKnownTypes = map[types.Kind]string{
+ types.AnyKind: "google.protobuf.Any",
+ types.BoolKind: "google.protobuf.BoolValue",
+ types.BytesKind: "google.protobuf.BytesValue",
+ types.DoubleKind: "google.protobuf.DoubleValue",
+ types.DurationKind: "google.protobuf.Duration",
+ types.DynKind: "google.protobuf.Value",
+ types.IntKind: "google.protobuf.Int64Value",
+ types.ListKind: "google.protobuf.ListValue",
+ types.NullTypeKind: "google.protobuf.NullValue",
+ types.MapKind: "google.protobuf.Struct",
+ types.StringKind: "google.protobuf.StringValue",
+ types.TimestampKind: "google.protobuf.Timestamp",
+ types.UintKind: "google.protobuf.UInt64Value",
+ }
+)